I was thinking about this but Beast formers could be a potentially interesting concept to explore in a One sequel
Because Obviously they exist, Trion turns into a robotic lion and Onyx's presence implies there's more of them, question is where are they?
I would suspect the reason they are not present in the film is because either Sentinel and the Quintessons drove them to near extinction or perhaps Sentinel sold them to the Quintessons as slaves (which could explain where the Sharkticons come from)
Or perhaps instead in an extension of Sentinel's caste system (and taking a cue from idw), the beast formers are the lowest of the low, treated literally like animals and forced out of society
In any case, it would be neat to see a sequel introduce surviving beast tribes comprised of the classic G1 beast formers, y'know, the mini-cassettes, Dinobots, Insecticons, Predacons, Terrorcons, Seacons, the Decepticon Headmasters (who were all beast formers), Horrorcons, Firecons, the Monsterbots, etc, and explore why they chose the side they did (more specifically why so many of them chose the Decepticons), and in the Dinobots' case, maybe have them initially join the Decepticons only to switch sides for the Autobots
